Spent Catalyst - Solid catalytic materials play major role in oil refining industry.Once catalysts completes their life cycle they will be withdrawn from the process, at this stage, catalysts are considered “spent” and the heavy metals, coke, and other poisonous elements make them as hazardous waste Catalysts gradually lose their catalytic activity, usually through structural changes, poisoning, overheating or the deposition of extraneous material. A catalyst is “spent” when it no longer exhibits the necessary activity or specificity required by the user.: In many refineries, the spent catalysts discarded units form a major part of these solid wastes. Disposal of spent catalysts requires compliance with stringent environmental regulations because of their hazardous nature and toxic chemicals content. 'REVA PROCESS TECHNOLOGIES' can suggest Depending primarily upon the chemical and structural changes in the catalyst during use the appropriate solution to deal with spent catalyst out of the following options.